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We measured magnetic moments of various s-wave superconductors. The paramagnetic moment was found in a superconducting Nb disk as obtained by other group. However it was not found in Pb disk. And we measured the cylindrical superconductors with and without’slits. A large difference between these samples was observed. We consider that the mechanism of these behaviors is flux compression as predicted theoretically.

The Meissner effect in the normal metals induced by the proximity effect of Nb has been investigated in relation to the Kondo effect for Cu with dilute magnetic impurities: Mn and Fe, Co, Ni. The thickness ρ of the Meissner region in Cu/Mn becomes nearly constant at low temperatures due to the magnetic scattering. The data provide a spin-flip scattering probability per 1 ppm Mn of about 5·109s−1. A study was also made of the proximity effect for heavy-fermion materials: CeAl3 and CeCu6. No measurable Meissner effect was observed in these materials.